Title (fr)

Publication

Application

Priority

JP 10994399 A 19990416

Abstract (en)

Black magnetic particles having an average particle diameter of from 0.1 to 0.3 mu m, which comprises: (a) black spinel iron oxide particles as core particles; and (b) a coat comprising spinel iron oxide particles provided on the surface of each core particle, the content of FeO in a surface layer having a thickness of from the surface of each black magnetic iron oxide particle to about 3.5% of the radius of the particle, being from 8 to 14% by weight based on the weight of Fe contained in the surface layer. <IMAGE>